Why Are Those Furniture Screws So Hard to Drive?

Why are the screws that came with my kit furniture so tough to drive?Fred M., Chattanooga, Tennessee

Most kits include something called confirmat screws, large dowel-like fasteners with a coarse auger thread. They're used with particleboard and predrilled holes. Usually, they're easy to drive. I could see where problems with the pilot hole would cause the problem you describe. But there may be other causes.

As obvious as it sounds, first read the instructions. Double-check for subtleties that could throw you off, such as panels that look nearly identical but have pilot holes in different locations. Assuming you've assembled the furniture per the instructions, stop driving if the screw gets stuck. Back it out and extend the pilot hole.

Finally, be sure you're using the correct drive bit. Most confirmat screws are meant to be driven with a Pozidriv bit. Like a Phillips bit, Pozidriv bits look like a plus sign. But the main ribs of the bit are more vertical, and there are smaller ribs to fit into side channels for a tighter grip. Pozidriv bits are designed not to cam out, or slip off the fastener's head. A Phillips bit, on the other hand, is designed to cam out once a specified level of tightening torque is reached. Translation: The Phillips bit will likely slip off the head of a Pozidriv confirmat screw, and you will get frustrated.

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